$\dfrac{6}{2} - \dfrac{1}{3} = {?}$
$ = {\dfrac{6 \times 3}{2 \times 3}} - {\dfrac{1 \times 2}{3 \times 2}} $ $ = {\dfrac{18}{6}} - {\dfrac{2}{6}} $ $ = \dfrac{{18} - {2}}{6} $ $ = \dfrac{16}{6}$